MASTERS THESIS DEFENSE

REMOVAL OF LUNAR DUST INSIDE CONFINED SPACE AND

EFFECT OF SHAPE IRREGULARITY ON PARTICLE

MIGRATION

Presented By

Prashant M. Ghadge

Advisor : Dr. Xianchang Li

Department of Mechanical Engineering

(Lamar University, Beaumont, Texas)

Part I

Tracking of Irregular Shaped

Particle

Part II

Modeling and Simulation

of Lunar Dust Remover

PART I: TASKS

1. Literature review

2. Effect of shape on force coefficients

3. Tracking algorithm

4. Application of UDF

5. Particle tracking

6. Results

Various Shapes

STUDY OF SHAPE

Source:<www.sandgrains.com>

Moon dust from Apollo 11

MOTION STUDY

ΔT

ΔT

Translation

(CD & CL)

Rotation

(T & θ)+

(Time Step)

From θ T

α=T/I

ω = ω0 + αt

θp = θ0 + ωt + ½ αt2

θf = tan-1(Vyrel/Vxrel)

θ = θp - θf

θ CD and FD

θ0 = θ and ω0= ω

Steps

or

Domain

TRANSLATION

STOP

START

I, m, θ, CD, CL & T

CD & CL

Y

N

MODEL TO STUDY TRANSLATION

V

Elliptical barrier tilted

at different angle

0.05 X 0.1 m

2D flow path

Elliptical Barrier

X

Y

FORCES ACTING ON THE BARRIER

FD = Drag force (N)

FD = CD 1/2 ρ V2 A

FL = Lift force (N)

FL = CL 1/2 ρ V2 A

CD = Drag coefficient

CL = Lift coefficient

ρ = Density of fluid

V = Flow velocity

A = Characteristic frontal

area of the body

Drag

Lift

Gravity

Velocity vectors at elliptical barrier

VARIATION WITH ANGLE

Variation of Coefficient

of Drag

Variation of Coefficient

of Lift

VARIATION OF CD WITH ANGLE

From θ T

α=T/I

ω = ω0 + αt

θp = θ0 + ωt + ½ αt2

θf = tan-1(Vyrel/Vxrel)

θ = θp - θf

θ CD and FD

θ0 = θ and ω0= ω

Steps

or

Domain

ROTATION

STOP

START

I, m, θ, CD, CL & T

Torque T

Y

N

STUDY OF TORQUE

Torque = Force × Displacement

Pressure Force Shear Force

VARYING TORQUE WITH ANGLE

UDF FOR ELLIPTICAL PARTICLE

Relative Angle

Relative Reynolds

Number

Drag

Lift

STRAIGHT CHANNEL

Spherical

Particle Track

Comparison of

Spherical & Elliptical

Particle Track

6.4

0 Sec

ELBOW CHANNEL

133

0 Sec

5m

5m

X

Y

Spherical

Particle Track

Comparison of

Spherical & Elliptical

Particle Track

From the study of forces

CD and CL decreases with Re

T increases with Re

Graph follows similar pattern

SHAPE is important factor

RESULTS AND DISCUSSION

Dust

Remover

Air

Filter

Enclosed

Capsule

WallOuter Door

Inlet

Outlet

Inner Door

PART II : LUNAR DUST REMOVER

Blower

BOUNDARY CONDITIONS AND PARAMETERS

Boundary Conditions

1. Inlet : Velocity inlet

2. Outlet : Pressure Outlet

3. Sidewall : Wall

4. Object : Wall

Parameters

1. Velocity = 4 m/s

2. Swirl components :

Radial = 0.3

Tangential = 0.3

Axial = -1

3. Re = 250,000

0 Sec

18

RECTANGULAR MODEL

Pro-E model

Velocity Pathlines

Simple flow

Particle Track

Swirl flow

CYLINDRICAL MODEL

Pro-E model

Particle Track

Simple flow

Velocity Pathlines

Swirl flow

0 Sec

11.8 1

0 m/s

MORE DUST REMOVER MODEL

Pear Shaped ModelDome Shaped Model

DOME SHAPED MODEL

Particle track

Swirl flow

Velocity pathlines and vectors

Simple flow

PEAR SHAPED MODEL

Particle track

Swirl flow

Velocity vectors

Swirl flow

Model Flow type

Particle Escaped

out of 100

In 30 Sec. In 60 Sec.

RectangularSimple 28 37

Swirl 30 54

CylindricalSimple 52 75

Swirl 32 50

Dome ShapeSimple 85 89

Swirl 57 87

Pear ShapeSimple 47 49

Swirl 100 100

COMPARISON: PARTICLE ESCAPED

COMPARISON OF MODELS

Particles

Removed

Out of 100

Models

From the study of Lunar dust remover

Pear Shaped Model:

I. Particle Escaped = 100

II. Maximum Time = 21 Sec

III. Mass of Air Needed = 12.6 kg

IV. Better Design

RESULTS AND DISCUSSION

CONCLUSION

1. UDF for lift, drag and torque

2. Tracking of elliptical particle

3. Model: Pear shaped

4. Flow: Swirl

THANK YOU